tri5ron
05-17-2009, 02:40 PM
Subject: Hydraulic Lifters
I've seen a "collapsed" lifter before,...
But have you ever seen a lifter stuck in the fully extended position?
Here's the scenario...
I take my boat out of a 4 month storage.
It is an old Mercruiser 4 cyl. 120 hp I/O.
Drained fuel prior to storage, ran the carb dry removed battery, etc.
Now,...
Filled w/ fresh gas, installed fully charged battery, primed carb, Hooked up water fitting, etc.
I go to start it, and it is extreemly hard to turn over. kind of like it has water in a cylinder, (but that is not the case).
I crank it a couple of more turns, Again, hard to turn over, but it does fire.
It seems to be running a bit rough, but I give it a minute to warm a little, and is begins to smooth out.
next thing I hear is a abnormal "Clattering" sound in in valve cover. It is running, but not smooth like it should, and the clattering stops.
I start pulling plug wires, and when I pull #2 wire, it does not effect the engine at all. (pulling #1, #3, #4, wires will kill the engine).
I shut it down, and pull the valve cover, to find that one of the Rocker arms for #2 cylinder has come off of the pushrod/valve, and is turned sideways.
I turn the Rocker arm back to it's proper position, to find that it has WAAYYY too much slack. (BTW, the pushrod is straight, and is NOT bent).
That's when I realize that the Stud, for the rocker arm, has been pushed up about 1/4 inch, out of the head casting, (The studs are apparently a "Pressed in fit", into the head casting).
This is what is causing the excessive slack.
I call a "Boat Guru" buddy of mine, (he used to have a Marine Repair Shop), and he says he has seen it happen on this particular engine a few times before, and that there is actually a Threaded Rocker Stud available to replace the Pressed in Stud.
O.K., That's a good thing, and I'm fine with that,..
(I'm just happy it did'nt snap the cam shaft or something worse!)
But my question is,...
Have you ever seen a Hydraulic Lifter get stuck,
in the "Fully Extended" position ?
Naturally I will replace the suspect Lifter at the same time I install the Threaded Rocker Stud,...
I may even just go ahead and replace al 8 lifters, since they are fairly easy to access.
So have any of you guys seen this happen on older (1971 era) Mercruiser in-line engines before ?
(or any OTHER engine, with Hydraulic Lifters, for that matter ???)
Inquiring Minds want to Know....
I've seen a "collapsed" lifter before,...
But have you ever seen a lifter stuck in the fully extended position?
Here's the scenario...
I take my boat out of a 4 month storage.
It is an old Mercruiser 4 cyl. 120 hp I/O.
Drained fuel prior to storage, ran the carb dry removed battery, etc.
Now,...
Filled w/ fresh gas, installed fully charged battery, primed carb, Hooked up water fitting, etc.
I go to start it, and it is extreemly hard to turn over. kind of like it has water in a cylinder, (but that is not the case).
I crank it a couple of more turns, Again, hard to turn over, but it does fire.
It seems to be running a bit rough, but I give it a minute to warm a little, and is begins to smooth out.
next thing I hear is a abnormal "Clattering" sound in in valve cover. It is running, but not smooth like it should, and the clattering stops.
I start pulling plug wires, and when I pull #2 wire, it does not effect the engine at all. (pulling #1, #3, #4, wires will kill the engine).
I shut it down, and pull the valve cover, to find that one of the Rocker arms for #2 cylinder has come off of the pushrod/valve, and is turned sideways.
I turn the Rocker arm back to it's proper position, to find that it has WAAYYY too much slack. (BTW, the pushrod is straight, and is NOT bent).
That's when I realize that the Stud, for the rocker arm, has been pushed up about 1/4 inch, out of the head casting, (The studs are apparently a "Pressed in fit", into the head casting).
This is what is causing the excessive slack.
I call a "Boat Guru" buddy of mine, (he used to have a Marine Repair Shop), and he says he has seen it happen on this particular engine a few times before, and that there is actually a Threaded Rocker Stud available to replace the Pressed in Stud.
O.K., That's a good thing, and I'm fine with that,..
(I'm just happy it did'nt snap the cam shaft or something worse!)
But my question is,...
Have you ever seen a Hydraulic Lifter get stuck,
in the "Fully Extended" position ?
Naturally I will replace the suspect Lifter at the same time I install the Threaded Rocker Stud,...
I may even just go ahead and replace al 8 lifters, since they are fairly easy to access.
So have any of you guys seen this happen on older (1971 era) Mercruiser in-line engines before ?
(or any OTHER engine, with Hydraulic Lifters, for that matter ???)
Inquiring Minds want to Know....